The invention pertains to the general field of motor vehicle exhaust piping and more particularly to a universal pipe joint that permits connection with angular alignment of two mating pipes and that may be secured in place with a set screw.
Previously, many types of universal joints have been used to provide an effective means to align two pipe ends when they are not exactly in a linear geometry. In the field of motor vehicle exhaust piping, connections are usually made by expanding one pipe end, and slipping the other end inside and then connecting by clamps or welding the joint together. Prior art has not fully satisfied this need by providing a universal joint that is reasonably inexpensive and simple in construction, as most presently available prior inventions use rather complicated rings, threads and radial surfaces to correct pipe misalignments.
A search of the prior art did not disclose any patents that read directly on the claims of the instant invention, however the following U.S. patents are considered related:
Witte in U.S. Pat. No. 5,101,915 teaches a pipe joint that can be used for joining pipes or tubing of all types by using an adjustable angle joint with a double set of threads on each end and a seal inbetween.
U.S. Pat. No. 4,556,227 issued to Sato, et al. discloses a universal pipe joint which uses a connector housing with a main cavity defined by an internal spherical concave wall, thus forming a connector housing body. A pair of axially spaced spilt rings, with inclined external walls, are in contact with the concave walls. Each of the split rings are deformable so as to be inserted into a main cavity and expand to an operating position with a spacer seal ring sandwiched between the rings.
Miyaoka in U.S. Pat. No. 3,938,833 discloses a pair of articulating rings fitted over the open ends of pipes. A spherical convex outer surface on each ring engages a pair of concave inner surfaces on the coupling. A sealing member is provided between each pipe and articulation ring. For attachment, each ring is provided with an internal annular groove receiving split lock ring, which engages external screws in the pipe using the internal annular groove in the pipe to receive the screws. A recess engaged by the lock ring attaching an articulation ring to one of the pipes, is made axially wider than the lock ring to permit relative axial. movement at the joint.
U.S. Pat. No. 3,931,992 issued to Coel discloses a connector having a tail piece with a ball end and a socket adapted to be snapped over the ball end with a coupling nut threadably engaging a pipe that is connected thereupon. The nut is threaded into engagement, thus urging the socket into a fluid seal, regardless of the angular disposition of the tail piece relative to the pipe element.
Misaligned exhaust piping has been a problem in the automotive industry since the inception of engine driven motor vehicles. In the past exhaust systems were relatively simple, with exhaust tubing leaving the engine manifold and passing under the vehicle to a muffler and then on through a simple tail pipe. With any, internal combustion engine the exhaust expelled contains noxious emissions which create health hazards. In order to combat this problem, environmental controls were introduced that required the use of a catalytic converter in the exhaust line upstream of the muffler. Making matters worse automobiles were basically smaller and dual exhaust systems became more popular. This created alignment problems in the aftermarket replacement field as exhaust lines were shorter, components larger, and often replacement parts are generic and not exactly the same configuration as the original parts. Further, the use of flexible exhaust tubing, which was previously popular, has diminished due to corrosion problems and in some cases government regulations.
In view of the above disclosure, it is the primary object of the invention to provide a universal joint that requires very little length in the exhaust line and is easy to install in a conventional manner using an internal slip fit of the pipe which permits the joint to be connected normally and allows misalignment up to 15 degrees.
Another object of the invention is that when the pipe joint is installed it may be locked in place with a simple hex key, thus precluding loosening of the threaded portion of the compression nut by vibration of the vehicle during use.
An important object of the invention is that conventional tools may be used for installation. Wrenches used for flat surfaces such as hexagonal nuts and the like and hook like spanners used in the exhaust system industry are utilized along with hex keys which are abundantly available.
Still another object of the invention is that the joint is formed of only three basic elements, all of which are uncomplicated and economically manufactured. An inexpensive ball, spring and lock screw are required to complete the device, thus allowing the invention to be within the economic reach of all.
Yet another object of the invention is its adaptability. By the addition of a resilient radial compression gasket the universal joint may be used with pressurized fluid such as a liquid, thereby expanding its utility to other fields such as plumbing and gas piping.
These and other objects and advantages of the present invention will become apparent from the subsequent detailed description of the preferred embodiment and the appended claims taken in conjunction with the accompanying drawings.